Electronic calculator



Dec. 8, 1953 B. J. CHROMY EI'AL 2,661,899

ELECTRONIC CALCULATOR Filed July 12, 1946 7 Sheets-Sheet 1 INVENTORS 336 CUT OFF A V Dec. 8, 1953 B. J. CHROMY ET AL ELECTRONIC CALCULATOR Filed July 12, 1946 7 Sheets-Sheet 2 v I m 1 EH L w w i Em 4 x Q mmm R 5 WmQ N\ v wwwm \QJEIJ W3 T W L W v MN INVENTORS MWA 7 Dec. 8, 1953 B. J. CHROMY ET AL 2,661,399

ELECTRONIC CALCULATOR Filed July 12, 1946 '7 Sheets-Sheet 5 /N l/E N TORS Dec. 8, 1953 B. J. CHROMY ET AL 2,661,899

ELECTRONIC CALCULATOR Filed July 12, 1946 v Sheeis:Sheet 4 Dec. 8, 1953 B. J. CHROMY ET AL 2,663,899

ELECTRONIC CALCULATOR Filed July 12, 1946 7 Sheets-Sheet s l I I r I I i l /N 1 5 N TORS Dec. 8, 1953 B. J. CHROMY ET AL 61,899

ELECTRONIC CALCULATOR Filed July 12, 1946 '7 Sheets-Sheet 6 oo ouno one ooaoaooo ono 0000000 INVENTORS Dec. 1953 B. J. CHROMY ET AL 2,661,899

ELECTRONIC CALCULATOR Filed July 12, 1946 '7 Sheets-sheaf, 7

INVENTORS Patented Dec. 8, 1953 ELECTRONIC CALCULATOR Benjamin J. Chromy, Washington, D. (3., and Philip H. Allen, Orinda, Calif.

Application July 12, 1946, Serial No. 683,200

33 Claims. 1

This invention relates to registers in general. More particularly, this invention relates to registers employing electronic selection devices the operation of which is controlled from a main pulse generator.

An object of this invention is to provide a register including selection mechanism consisting of an electron tube having a target on which various numeral orders may be set or flashed.

Another object of this invention is to provide a register having an electron tube with a light sensitive target which may be scanned by an electron stream to provide electric pulses in the output circuit of the electron tube in accordance with the various ordinal numbers projected by light beams on the light sensitive target of the electron tube.

Still another object of this invention is to provide an electron tube having a target upon which light spots or indicia may be projected for scanning by an electron stream to produce electrical pulses in the output circuit of the electron tube in accordance with the light spots on the target and in accordance with the scanning of the target.

Another object of this invention is to provide :a light sensitive electronic device adapted to pro- :duce electric pulses in the output thereof in ac= cordance with values set into a keyboard associated with the electronic device, the aforesaid electric pulses being fed to an electronic switching device which is connected to a plurality of orders of register tubes.

Still another object of this invention is to provide an electronic register having a plurality of electron tubes in which streams of electrons :are scanned over targets for generating electric pulses and for register switching, the electron streams of these electronic devices being controlled in their scanning operation from a central electric pulse generating apparatus.

A further object of the invention is to provide a register incorporating a light responsive selection mechanism providing an output representative of values represented by light indicia on the screen.

Still another object of the invention is to provide light sensitive selection mechanism to receive light indicia representing both digitation and transfer values and to provide an output correspondin to these values for entering a register.

A further object of the invention is to provide alight responsive selection mechanism including ascreen upon which ordinal values can be repre sented for both digitation and tens transferring operations.

A further object of the invention is to provide selection mechanism in the form of a cathode ray tube incorporating a light responsive screen upon which ordinal values can be displayed for both tens transfer and for digitation and also incorporating means for operating the counter which records the cycles of operation of the machine.

Other objects of the invention will be apparent from certain preferred embodiments of the invention.

Referring to the drawings briefly,

Figure 1 is a sectional elevational View of a calculating machine embodying this invention.

Figure 2 is a fragmentary sectional view of the cathode rav scanning device and electrical circuits associated therewith employed in accordance with this invention.

Figure 3 is a detail sectional view of the light control and optical apparatus for nroiecting light spots upon the screen of the cathode ray scanning device.

Figuie 4 is a fragmentary sectional view of the shutter devices employed in the light control apparatus shown in Figure 3. V

Figure 5 is a schematic wiring diagram of the saw-tooth wave generators connected to the cathode ray beam deflecting devices of the cathode ray scanning apparatus.

Figure 6 is a schematic wiring diagram of a portion of the register apparatus and associated circuit.

Figure 6a is a diagram illustrating the character of the scanning pulses employed with the circuit of Figure 6.

Figure 7 is a schematic wiring diagram of the steo-by-step counting circuit.

Figure 7a is a schematic wiring diagram of the means for varying or shifting the ordinal position of entry of digits into the accumulator.

Figure 8 is a schematic wiring diagram of the circuit providing for ordinal entry of the respective series of ordinal pulses obtained from the selection mechanism.

Figure 9 is a schematic wiring diagram of the blanking circuit for the cathode ray of the selection tube.

Figure 10 is a schematic wiring diagram of a modified form of control for the switching tube.

Figure 11 is a schematic Wiring diagram of a modified form of tens transfer circuit.

Figure 12 is a schematic wiring diagram of General description The present invention is concerned generally with providing a selective pulse generator es the plural order selection mechanism of a register, such as a calculating device, for example, in which the various values to be entered into the register or accumulator may be represented in the form of an ordinal arrey of light indicia, such as light dots, on the light-responsivescreen of a cathode ray tube. Associated with the cathode ray tube is a scann ng circuit adapted to produce a step-by-step scanning of the ordinal array of light indicia on the screen and at the same time to control a sweeping circuit whereby the pulses resulting from scanning of the respective ordinal arrays of light indicia will be introduced successively into the various orders of the electrical registering devices or tubes.

Also the invention contemplates the exercise of a tens trensfer control from the registering tubes of the accumulator to place additional light in dicia on the screen in the correct ordinal positions to represent tens transfer increments which will be scanned with the other ordinal lighting lndicia of the same order representing the digitation values of this order. Further, the scanning of the screen is utilized to provide a counting pulse so that the cycles of the operation can be counted and entered .into a counter register in the appropriate ordinal positions.

Selection mechanism Keyboard and optical selecting -system.-Referring to Figure 1 of the drawing in detail, reference numerals H), II, l2, l3, l4, l5, IS, H, H) and I9 designate a row of values keys-0 to 9, respectively, of the first order of this apparatus. The value keys It to IE are of conventional construction and each has associated therewith a compression spring for maintaining the key in its raised or uppermost position. Also associated with the row of keys is a latching slide 2!! of conventional construction which is provided with a spring 2! bywhich it is urged to active position. The latch slide is adapted to cooperate with the keys in the usual manner to hold a depressed key in its depressed position until it is released by the depression of a subsequent key.

Associated with each ordinal row of value keys is a selection or cam slide 22 of conventional construction which is supported by pivoting links 23 and 24 directly beneath the lower ends of the key stems H to Iii, inclusive, and this cam slide 22 is provided with cam surfaces 3| to 39, inclusive, portions of these surfaces being adapted to be engaged by the key stems I0 to Hi, inclusive, respectively, whereby the member 22 may be moved endwise differential distances by the different keys II to I9, inclusive.

A lever 25 is attached to the pivoted member 24 to form a bell crank which is part of the mechanical linke ge between the selection slide 22 and, a shutter manipulating plunger 26 that is pivotally attached to the lever 25 by a pin 21 engaging a slot 28 of the lever 25. The 11.11. 1 .56 26, shown in 4 greater detail in Figures 3 and 4, is U-shaped member slidably mounted in the housing 29 so" that this plunger may be moved upward through smell incremental distances as the lever 25 is moved upward. As the lever 25 is moved upward, the plunger 26 is moved in linear fashion in the apertures of the housing 29 provided therefor. The plunger 25 is provided with a plurality of differentially spaced pins 4| to 59, inclusive, for engaging levers 5| to 59, inclusive, respectively, of the shutters 6| to 69, inclusive, respectively. The shutters 6| to 69, inclusive, are associated with aperture systems I! to 9, inclusive, respectively and with lens systems 8| to 89, inclusive, form light collimating systems for passing small bee ms of light from the light source and when the shutters 6| to 69, inclusive, are closed these beams of light impinge upon light absorbing surfaces of carbon or the like, provided to these shutters. However, when the number 9 key it is in depressed position and the lever 25 of the bell crank is in its uppermost position so that the shutters 6| to 68, inclusive, are open light beams collimated through all of the aperture systems H to 19, inclusive, pass substantially unobstructed through the lens systems 8| to 89, inclusive, respectively, and are focused upon the light sensitive or cathode mosaic of the oathode ray beam device 92. As a result, nine light spots will appear upon the screen 9| of the device 92. However, if only the one key of the keys It! to l9, inclusive, is depressed, only the shutter 6| is opened because of the cam device 22 is moved only a small distance in its lateral movement and the lever 25 of the bell crank moves the plunger 26 only far enough so thst the pin M deflects the shutter 6| out of the path of the light beam passing through the aperture system i i. At the same time and because the difierential spacing of the pins 4| to 49, inclusive, the one-step movement of the slide to open the shutter 6| has moved the pin 42 on the plunger 26 into engagement with the lever 52. Correspondingly, additional increments of movement of the selection slide 22 upon depression of the higher value keys will cause additional ones of the series of p ns 4| to 49 to become effective and to correspondingly open additional ones of the shutters ti to 69. In this way, a corresponding number of light rays can be enabled in each order of the selection mech anism in accordance with the value of the depressed value key to Hi. This selective control of the li ht beams is enabled because the lever 25 moves through progressively increasing angles depending upon which of the keys H to IS, inclusive, respectively, are depressed. It will be observed that the pins 4| to 49, inclusive, of the plunger 26 are spaced by different distances from that by which the levers 5! to 59, inclusive, of the shutters 6! to 69, inclusive, respectively, are spaced. Consequently, the pin l! engages the lever 5| before the pin 42 engages the lever 52, and the pin 42 engages the lever 52 before the pin 43 engages the lever 53, and so on, until the pin 49, being the last of the series of pins, engages the lever 59 after all of the other pins have engaged 2nd lifted their respective levers. Consequently, the shutters 6| to 59. inclusive, may be deflected out of the path of the associated light beams in series, the shutter 6| being deflected first. shutter 62 being deflected second. while the shutter 6| is held open, the shutter 63 being deflected th rd, while the shutters t! and 2 are held open and the shutter 64 being deflected fourth while the shutters El, 62 and as are held open,

published by John Wiley and Sons, Inc.

acetone 5 and so on, until the shutter I59 is deflected while the shutters 6! to 58, inclusive, are held open.

.A plurality of rows of keys, such as keys In to I9, inclusive, are provided and each of these rows is associated with a cam slide, such as 22, a crank, such as 25, and a shutter operating plunger, such as 26, so that each row of keys may be operated to control from one to nine light beams through a shutter system, such as, shutters 6! to 5B, inclusive, aperture system, such as H to it, inclusive, and lens system, such as S! to 89, inclusive. Each row of aperture systems, such as H to F9, inclusive, is provided with an elongated light source, such as 90, which may be an elongated incandescent type lamp, or a fluorescent type lamp, or an ionized gas tubular lamp.

The lens systems iii to 89, inclusive, consist of a plurality of lenses and these may be made of such material as lucite, which may be formed by suitable dies. Where a plurality of rows of apertures, such as H to I9, inclusive, are posh tioned side by side so that a plurality of lens systems, such as 8! to 39, inclusive, are positioned side by side, all of the lens system elements lying in the same plane may be formed together by a single set or dies so that the lens systems form unitary self-supporting structures of a wall-like configuration, the edges of which engage the interior walls of the housing 29. The interior of the housing 29 may be coated with black, lightabsorbing substantially non-reflecting coating, such as carbon, or Aquadag to minimize refiections in the interior of the housing.

From the above description it is seen that in response to selective depression of the different orders of the keys of the dififerent orders of the keyboard, a plural digit factor may be entered into the machine and through the optical system associated with the housing 29 will be displayed on the light responsive screen 9! in the form of an ordinal series of incremental light indicia or dots corresponding in value to the values of the depressed keys of the keyboard.

Selection tuba-As previously stated the cathode ray device 92 including the screen ill is adapted to scan the light indicia on the screen and to transmit pulses from the output thereof which will be representative of these ordinal values. This scanning is controlled in cyclic fashion and. there are respective vertical scanning sweeps for the successive ordinal positions on the screen while one transverse cyclic sweep is taking place.

The cathode ray device 82 may consist of a device, such as the Iconoscope or it may consist of a Farnsworth disector tube, or a photoconductive pick-up tube, such as are described in the book Television by Zworykin and Morton, This tube is provided with a glass envelope having a filament 93 connected to a source of current sup ply, such as transformer 95a, and provided for the purpose of heating the electron emitting cathode 94. The cathode 84 is connected to an intermediate point on the battery 95 and the negative terminal of this battery is connected through the blanking apparatus 245 to the control electrode 95 anode a1 and the third anode 99 is connected to the positive terminal of the battery 95 so that the third anode 99 is positive with respect to the second anode 98 and the first anode 91.

The heater filament 93, cathode '94, control electrode 56, first anode 91 and second anode 98 comprise the electron gun of the cathode ray device 92 and this electron gun provides the cathode ray beam or electron beam that is used to scan the cathode mosaic screen 9| upon which the light beams from the light collimating, control and focusing devices in the housing 29 are proiected to form light spots. It is apparent that while a rather elaborate type of cathode ray device 92 is illustrated, a much simpler device may be employed in this invention inasmuch as the high definition such as is required in television is not required in the present invention. Conse quently, a much simpler electron gun than that illustrated may be employed.

Scanning pulse generator.-Referring to Figures 5 and 6 in detail, there are illustrated the circuit connections of the saw tooth current generators which are shown in block form and designated by reference numerals Hit and it! in Figure 2. The saw tooth generator use is connected to the electromagnetic deflecting coil I62 of the electron beam device 92 to provide a cyclic transverse sweep of the beam and the saw tooth generator IIJI is connected to the electromagnetic deflector I03 of this device to provide a plurality of ordinal vertical sweeps of the beam during the cyclic sweep. It is, of course, obvious that electrostatic deflection of the electron beam of the device 92 generated by the electron gun thereof, may be used for moving this beam over the screen 95 instead of the electromagnetic deflection apparatus illustrated.

In the circuit arrangement shown in Figure 5 there is provided a thermionic electric discharge device I04 of the pentode type having a cathode I05; cathode heater its, a control grid I07, a screen grid H38, a suppressor grid I09 and an anode Its, and this device Hid is employed for the purpose of charging the capacitor III through the resistor H2 from the source of current supply H3. A source of grid bias potential ll t shunted by the potentiometer I I5 and having one terminal thereof connected to the cathode 65 is employed for controlling the charging of the capacitor ill through the tube EM. For this purpose the single pole double throw switch H8 having the blade thereof connected to the grid iii! and the two contactors thereof, one connected to a terminal of the bias potential source I It and the other connected to the variable contact of the potentiometer I I5, is employed and the operation thereof will be described in detail hereinafter.

A thyratron Hi (Figure 5) is employed for discharging the capacitor HI and for this purpose the anode of this thyratron is connected to the positive terminal of the source H3 and the associated terminal of the capacitor Ill. The cathode of the thyratron ill is connected to one terminal of the resistor of the potentiometer us, one terminal of the source of grid bias po tential H9, one terminal of the resistor H2 and the anode H6 of the tube M34. The other terminal of the resistor of the. potentiometer H8 is connected to the negative terminal of the source of bias potential H3 and the variable contactor of the potentiometer I I3 is connected to the grid electrode of the thyratron Ill. The anode of the thyratron I H and associated terminal of the capacitor iii and battery H3 are connected 7 through the conductor I25 to the deflector elec trode I2I of the electron beam switching device I23 and to the capacitor I24 associated with the control grid of the thermionic device 125. The cathode of the thyratron H1 and anode iii of tube I06 are connected through the wire I25 to the other deflector I22 of the electron beam device I23 and to the cathode of the tube 125.

The purpose of the electron beam device !23 (Figure is to provide a definite number of pulses in the output circuit 121-428 thereof for each electrical pulse of saw tooth wave form applied to the deflectors I2I-I22 thereof. This electron beam device I23 is in general similar to the device 92 shown in Figure 2 in that it is provided with an electron gun consisting of a cathode I as, a control electrode I3il, and an anode lBI. Another electrode I32 which may be used either as an anode or as a quenching electrode as will be described in greater detail hereinafter, is also provided in the electron gun of the tube I23. The target of the tube E23 consists of a plurality of contacts I33 to M4, in-- clusive, connected to the busbar I51 and another similar set of contacts M5 to inclusive, connected to the busbar 158, the busbar 151 being connected to the output wire 123. These contacts I33 to 14%, inclusive and M5 to 553, inelusive, are associated in pairs, that is, contacts i33l45 comprise one pair, contacts N l-4E5 comprise another pair, ESE-4&1 comprise a third pair, contacts MiG-448 comprise a fourth pair, I31-I i9 comprise a fifth pair, Eta-I58 comprise a sixth pair, I39-I5i comprise a seventh pair, I56iI52 comprise an eighth pair, Hit-453 comprise a ninth pair, M2-i5 -l comprise a tenth pair, I43I55 comprise an eleventh pair, and Hi l-456 comprise a twelfth pair, so that as the beam is swept over these contacts, as will be described in detail, twelve pulses for each sweeping of the beam thereover will be applied to the output circuit i21--l28.

Simultaneously as a saw tooth shaped poten tial impulse is applied to the deflector electrodes I'M-422 of the electron beam device I23 the same potential pulse is applied to the input circuit of the thermionic device I since the conductors i219 and I25 are connected to the input circuit of this thermionic device. The purpose of the device 125 is to alter the shape of the saw tooth potential pulse produced by the charging of the capacitor III through the tube ills before this potential pulse is applied to the electromagnetic deflector coil 592 of the device 92. If electrostatic deflection is used in the device 52 instead of the electromagnetic deflection illustrated the thermionic device H25 may be dispensed with and the electrostatic deflectors of the device 92 employed for moving the beam laterally may be connected directly to the conductors Hit-126 to the output of the tube me. In other words, the thermionic device I25 is a current amplifier functioning to produce a saw tooth current wave for a circuit consisting of inductance and resistance in series.

The electron beam apparatus I23 is provided with a source of current supply H59 for energizing the electron gun thereof and for controlling the operation of the device. A single pole double throw switch 889 which is mechanically coupled to the switch i 56 but electrically insulated therefrom, is employed with the blade thereof connected to the electron gun electrode I32 and with the terminals MI and 552 connected to the resistor I3 and the positive terminal of the source of current supply I59, respectively. The other terminal of the high resistance I63 is connected to the negative terminal of the source of current supply I59 which is also connected to the control electrode I30 of the electron gun through the blanking resistor 258a. Thus, when the blade I68 of the switch contacts the terminal, H52 the gun electrode I32 is connected as an additional anode and functions to focus the beam of the electron gun upon the contacts of the target. However, when the switch blade I60 contacts the terminal IEI the electrode I32 is used as a beam quenching or blanking electrode.

The output conductors I21-I28 are employed to connect the apparatus I to the apparatus IBI shown in Figure 6 so that the latter apparatus may be triggered or pulsed by the tube I23 shown in Figure 5 to generate the vertical ordinal scanning pulses for the deflector coil I03 of tube 92. The apparatus IilI consists of a vacuum tube 154 having a cathode I55, grid electrode 5% and an anode I61. A grid resistor I10 is connected between the grid I and the lower terminals of the cathode resistor HI and cathode capacitor I12 to bias the tube [64 to cut off during the charging of the capacitor I13. One terminal of resistor IE9 is connected to the positive terminal of the source of bias potential I68 and the variable contactor of this resistor I69 is connected to the wire H21. The negative ter-, minal of the source of .bias potential I68 is connected to the lower terminals of the cathode resistor I15 and cathode capacitor I12 and the upper terminals of these devices l1I-I12 are connected to the cathode I65 and to the capacitor I13 and resistor I14. The other terminal of the capacitor I13 is connected to the anode I61 and to the top terminal of the variable resistor 515 as well as the output terminal I11 and capacitor 119. The negative terminal of the source of current supply I16 is connected to the cathode resistor I11 and to the output terminal I18 and the positive terminal of this source of current supply is connected to the resistors I14 and I15.

The anode I51 of the vacuum tube its is coupl d through the capacitor I19 to the control grid of the current amplifier tube 580 and the cathode of this current amplifier is, connected to the negative terminal of the source of current supply 515 and to the lower terminals of-the cathode resistor HI and cathode capacitor I12. The purpose of this current amplifier is substantially the same as that of the current amplifier 525 as described above. The anode of the current amplifier llii is connected to the output terminal l8! and through this to one of the terminals of the electromagnetic deflector coil 103 of the electron beam device Q2. The cathode of the current amplifier I89 is connected to the output terminal 182 through anode battery IBM. The screen grid of the current amplifier 139 is coupled to the cathode by the capacitor 583 and the positive terminal of the battery Itlia is connected to the screen grid by the resistor little. The output terminal I82 is connected to the other terminal of the electromagnetic deflector coil Hi3 of the electron beam device 92.

The terminals I11 and 118 of the apparatus Ifii are connected to the step by step counting circuit 238 shown in Figure 7 consisting of the diode rectifier tubes i3 and I85 and the capacitor ltli. Each of the diode rectifier tubes I84 and E85 is provided with a cathode and an anode, the diode its having a cathode I86 and an anode E81 and the diode I85 having a cathode I88 and an anode I89. The anode 1829 of the diode I85 is connected to the cathde I96 of the diode I84 and to one terminal of the coupling capacitor I9 i, the other terminal of this coupling capacitor being connected to the terminal Ill. The cathode of the diode I85 is connected to the upper terminal of the capacitor I90 and to the grid of the triode I92. The anode I87 of the diode I34 is connected to the terminal I I8 and to the lower terminal of the capacitor I96 and also to the negative terminal of the battery I99. The negative terminal of the battery I93 is also connected to a high resistance grid resistor I 94 to apply a negative bias to the grid of the triode I92 whereby this tube I92 is biased nearly to cutoif since the positive terminal of the battery I93 is connected to the cathode of the tube I92. The anode of the tube I92 is connected to one terminal of the resistor I96 and to the deflector electrode I99 of the electron beam switching tube I 9?. The other terminal of the resistor I96 is connected to the other deflector electrode I98 of the tube I97 and to the positive terminal of the battery I95, the negative terminal of this battery being connected to the cathode of the tube I92. The tube I92 is of the remote cutoff type having a grid voltage plate current characteristic of a substantially exponential shape. The reason for using a tube I92 of these characteristics is to compensate for the non-linear charging of the capacitor I 99. The capacitor I90 is charged in step that decrease in size exponentially as the voltage across this capacitor approaches the final value and the characteristic of the tube I92 is such as to compensate for this exponential decrease in size and produce in the output circuit thereof across the resistor I99 voltage steps of substantially equal size.

The blanking apparatus 225 is also shown in detail in Figure 9 and consists of an amplifier 249 having a cathode 24?, a grid 248 and an anode 249. The grid 298 or the amplifier 255 is coupled by capacitor 2492 to the terminal 25I of the saw tooth generator apparatus IOI and the cathode 247 is connected to a terminal of the cathode follower resistor 25% and to a terminal 252 of the apparatus 12!. These terminals 25I and 252 are connected to the output terminals of the saw tooth generator i9I as shown and in this manner function to supply the input of the amplifier 246 with saw tooth-shaped electrical impulses, such as are supplied to the current amplifier I39 for sweeping the beam of the electron beam tube 92 vertically over the mosaic cathode iii. A source of anode current supply 255 having the positive terminal connected to the anode resistor 259 and the negative terminal connected to the cathode follower resistor 253 so that the anode current of the amplifier 256 fiows through the cathode follower resistor 256. The cathode of this amplifier 226 is connected to a capacitor 251 and the other side of the capacitor is connected to the control electrode 95 of the tube 92 and to the resistor 258. The other end of the resistor 252' is connected to the negative terminal of the battery 95 so that the potential between the electrode 99 and the cathode 99 is applied from the battery 95 through the resistor 258. The negative terminal of the cathode follower resistor 259 is coupled to the negative terminal of the battery 95' and the corresponding terminal of the resistor 258 by the capacitor 259. It will therefore be observed that the potential across the cathode follower resistor 259 corresponding to the saw tooth shaped pulses derived from the apparatus IBI is applied to the control grid 96 of the electron beam device 92 through a difierentiating circuit consisting of the capacitor 251 and the resistor 258 and this diirerentiating circuit functions to blank the electron beam of the oathode ray device 92 during the abrupt downward or return stroke of the electron beam of this device. For this purpose, this differentiating circuit is adjusted so that the voltage between the cathode as and the control grid 96 of the tube 92 is relatively constant while the beam of the device 92 is being scanned upward across the cathode mosaic 9I. However, when the beam of thi tube 92 reaches the top of the mosaic 9I the saw tooth pulse collapses relatively rapidly and as a result the potential on the control grid 96 is further decreased, that is, this control grid 96 is made more negative with respect to the cath- Ode 94 and the beam of the tube 92 is momentarily out 01f until the next saw tooth pulse is supplied by the apparatu IIlI at which time the beam of the tube 92 is restored and started on its next upward scan.

A similar blanking circuit is provided to the impulse producing tube I23 shown in Figure 5 and this consists of the triode 246a having cathode 24la, grid 248a and anode 249a. The triode 246a is supplied with saw tooth pulses through capacitor 298:1: from the output circuit of the pentode I M. The triode 246a is supplied with plate current from the battery 255a through the anode or plate resistor 256a and cathode follower resistor 256a and the cathode follower resistor is coupled across the blanking resistor 258a by capacitors 251a and 259a so that the beam of the tube I23 is blanked out during the return trace thereof after it has swept over the target electrodes I33I56 to produce 12 pulses in the output circuit I'll-I28. When the beam of the tube 623 is reestablished it is in position to begin another cycle, 1. .e.,' to produce 12 more pulses.

However, the beam of the tube 92 need not be blanked out through use of a circuit such as circuit 245 (Figure 9) since the resistor-capacitor circuit consisting of the capacitor 232 and the resistor 233 connected to the output of the tube 92 may be tuned or adjusted to respond to the time rate of the voltage pulse produced by the tube 92 during the upward or useful scan of the mosaic 9I by the electron beam. If the filter consisting of the capacitor 232 and resistor 233 is adjusted to the time rate of the aforesaid upward scan of the mosaic by the electron beam then this filter will reject the voltage pulses produced by the back swing or abrupt scan of the mosaic. The filter may be adjusted to electrical pulses of different frequencies and it may consist of different combinations of capacity, resistance and/or inductance. Furthermore. it be connected on the output of the amplifier 234- if desired and in that case the filter would obviously be provided in addition to the resistor 233 and capacitor 232 since these normally function as coupling capacity and grid resistor.

Switching tuba-As previously explained, the respective ordinal pulses generated by the oathode ray device 92 are entered successively in the register tube in the desired ordinal relation from the lowest through the highest of these tubes which are selected to be active. For this purpose, an electron beam switching tube is provided which operatesduring each cyclic scanning sweep.- to connect successively the output of the .cathode my device 9 2' to the respective input circuits of the register tubes. The ordinal position. of entry of the various digits or digit pulses may be varied it or controlled for multiplying or tion.

The electron beam switching tube l8? (Figure 8) is provided with a cathode 280 which is indirectly heated, a control electrode 2i, a first anode 202 and, a second anode 283. These electrodes comprise the electron gun which projects a beam of electrons between the deflector electrodes H8 and 953 to the target electrodes 2% to 227, inclusive. These target electrodes are ar ranged in pairs Ed t-2%, Zita-2M, 268-409, 2l0-2H, 2l2--2i3, 2l4-2l5, 236-411, Zia-2H], 220-22i, 222-223, 226-225, and 226-22l, and these pairs of target electrodes are connected to the pulse inserting resistors of the register tubes. For example, electrodes 20 l-2d5 are connected to the pulse inserting resistor 602 of the main deflector circuit of the units register tube Gill, target electrodes Hit-81 are connected to the pulse inserting resistor 102 of the tens register tube I target electrodes 2i38-2ll9 are connected to the pulse inserting resistor 202 of the hundreds register tube 8M, target electrodes 2 ill- 2H are connected to the pulse inserting resistor 902 of the thousands register tube Sill, etc.

Referring to Figure 2, the conducting plate 239 in back of the electron emissive sensitized target SI of the electron beam tube 92 is connected to the top terminal of the resistor 23l and to a terminal of the capacitor 232. The other terminal of the capacitor 232 is connected to the grid resistor 233 and to the grid electrode of the thermionic tube 234. The cathode of this thermdividing operaionic tube 234 is connected to the terminal 235 of the apparatus 23? and the lower terminals or" the resistors 23! and 233 are connected to terminal 236a. The anode of the tube 234 is connected to the terminal 235 of the apparatus 23? and the cathode of the tube 235 is connected to the terminal 23E of this same apparatus. The apparatus shown in the block 23'! in Figure 2 consists of the apparatus more completely shown in Figure 8 and it will be seen that the terminals 235 and 236 are connected to resistors 235a and 2M, respectively. The tube 234 is connected as a cathode follower tube including a resistor 24! connected between the cathode thereof and the negative terminal of the battery 2&2, the positive terminal of this battery being connected to the anode of the tube 234 through the resistor 234a and terminal 235. The cathode follower resistor 25! is connected across the grid resistor Mil through the capacitor 239 so that voltage pulses produced across the cathode follower resistor 2M are impressed across the grid resistor 24%) to key the electron beam of the electron beam device i9'i and thereby cause this electron beam to transmit pulses to selected pairs of electrodes 294-221 of the target of tube 59?.

Accumulator or register circuit The accumulator or register comprising the cathode ray tubes SM, 19!, 80!, 95!, mm and HM is of the character disclosed in our copending application, Serial No. 611,608, filed August.

register of a calculating or adding machine of the mechanical type. The register tubes are reversibe employed to obtain g2} ble in character and are responsive to both positive and negative pulses to perform addition and subtraction, respectively, as determined by the setting of controls of the apparatus. Also, tens transfer mechanism is provided to transfer increments or pulses from order to order, 1. e., from tube to tube, of the register as the transfers occur during the calculating operation. The cathode ray tube til! (Figure i l) is in general of the same type as cathode ray tube IS in that this tube is provided with an electron gun 6% for producing an electron beam and transmitting this beam substantially down the length of the tube. The beam passes between the deflector electrodes of the tube to complete the desired circuit at the righthand end of the tube and also activate the fluorescent figures or legends associated with the contactors at the right-hand end of the tube. Thus, the electron beam transmitted by the electron gun Eillii of the tube 60! passes between the deflector plates 66'? and EM, and after passing between the deflectors 5i and 698 the beam is employed to close the desired circuit associated with the contactors 689 to 618 and EMS! to 628. These contactors are arranged in pairs as follows: cue-em, tilt-E26, B! I52l, $52-$22, 6l3-623, 6M624, 655-625, Bit-626, tit-G21, and 6|862B, corresponding to digits from zero to nine, respectively, and these digits are outlined in fluorescent material on the inside surface 629 of the right-hand end of the tube as i The contactors see to M8, inclusive, are connected together to a bus 630 which is connected to the variable resistor tEi and to the deflector plate SE18. The electrodes 819 to 5323, inclusive, are connected to taps 532 to 56!, inclusive, respectlvely, of the voltage divider 642. The tap or terminal 63! of the voltage divider 6 32 is connected to the normally closed zeroizing or resetting key 643 and from this to the positive terminal of the battery the negative of this battery being connected to the resistor B32 and through this to the deflector plat 55?.

The above described register tube operates as described in said application in response to electrical signals or pulses to register a value corresponding to the number of pulses received thereby. The potential applied to the electrodes 60'! and see is a measure of the value registered.

Operation As previously mentioned, the value selecting apparatus 2%! functions to project light spots representing various ordinal values on the sensitized cathode 9! of the tube 92 and the electron beam projected from the electron gun of the tube 92 is caused to scan the surface of the target cathode 9| through the operation of the scanning potential generating apparatus Hit and liil. As this beam scans the light spot areas of the mosaic cathode 9!, the electrostatic charges applied to the grid of the amplifier tube 234; are varied in accordance with the aforesaid light spots so that the light spots projected on the mosaic cathode 9! are reproduced in the output circuit of the amplifier 23% in the form of electrical pulses and these electrical pulses control the electron beam of the tube lil'i, shown in Figure 8, so that the beam of the tube is? transmits these pulses to the target electrodes thereof.

It will be observed that the light spots are projected upon the mosaic cathode 9! of the tube 92 in vertical rows and these vertical rows corregangsta the electron gun of the tube 92 scans them selecgenerator 196 produces one saw-tooth impulse which functions to deflect the beam of the tube 92 laterally while the generator [01 which is tri gered or pulsed by the tube I23 produces twelve saw-tooth impulses which function to deflect the beam of the tube 92 vertically twelve times while the aforesaid beam is being deflected laterally once. Thus, the light spots of the first vertical row projected on the mosaic cathode 9| are translated into electrical pulses in the output of the tube 234 and applied to the control electrode 20! of the beam switching device [91, at the same time as the beam of the switching device I9! is positioned through the operation of the deflector electrodes |ea |ea on the first pair of contacts 204- 265. In this manner the electrical pulses corresponding to the first or right-most row of light spots projected on the cathode mosaic 9! are transmitted through the electrodes ace-295 to the deflector circuit of the first order register tube 601 through the resistor 602.

At the end of th vertical sweep of the cathode ray beam of the tube 82 across the mosaic cathode 9!, this beam is blanked out by the blanking cir cuit 245 which is also controlled by electrical pulses from the generator apparatus iili so that after the beam is swept upward over the mosaic cathode 91 it is not swept downward but instead is blanked out. When the beam of the tube 92 is restored, it is in position to move upward over the second row of light spots on the mosaic cathode inasmuch as the potential produced by the generator apparatus I99 applied to the coil 162 has increased sufficiently to move it to the next vertical row of light spots, i. e., the second order, and the second cycle of the generator apparatus Hll functions to sweep the beam upward over the second. row of light spots, thereby producing electrical pulses in the output of the amplifier tube 234 corresponding to the second row of light spots on the cathode mosaic 9i of tube 92. The second cycle of the generator apparatus is! also functions to charge the capacitor 599 as shown in Figure '7 with its second incremental charge, and this charge being applied to the deflector electrodes [GS-I99 of the switching tube i9! defleets the beam of this tube to the second pair of targetelectrodes 2136-28? which are connected to the deflecting circuit of the second order register Till so. that the electrical pulses corresponding to the light spots on the second vertical row on the mosaic cathode 9'! are transmitted to the second order register tube Jill. Thereafter, that is, when the beam of the tube 92 reaches the top of the mosaic cathode. 9| along the second row of light spots, the blanking circuit 265 is again operated and the beam of the tube 92 blanked out. When the beam of this tube is again restored, it is at the bottom of the mosaic cathode '91 in position to scan the third row of light spots and this row is scanned through the operation of the third sawtooth impulse transmitted to the deflector coil I53 from the generator apparatus Hll. Since this generator apparatus I 8| also furnishes the pulses to charge the capacitor 195 in step fashion, the third step "of the charge of this capacitor I90 functions to deflect the beam of the tube 191 to the third pair of electrodes 208-2El9 so that the electrical pulses corresponding to the third row of light spots on, the mosaic cathode Likewise, the electrical pulses corresponding-to the fourth row of light spots on the mosaic cathode 9! are transmitted to the fourth order register tube Bill and the electrical pulses corresponding to the fifth row of light spots on the mosaic cathode ill are transmitted to the fifth order register tube Ifilll, and so on. Twelve orders of register tubes may be employed with the apparatus as disclosed since the generator apparatus lfll proso that twelve rows of light spots may be posi- .91; are transmitted to the third order. register tube tioned on the mosaic cathode iii and scanned by the beam of the tube 92 for each lateral deflection of this beam. However, different numbers of rows of light spots other than twelve may be projected on the mosaic cathode 9! if desired, and diiferent numbers of saw-tooth pulses other than twelve may be generated by the apparatus I ill for each pulse generated by the apparatus W8 and this is controlled by the number of pairs of target electrodes 133-156 provided to the tube 123. Thus, if more than twelve pairs of electrodes are provided to this tube, a correspondingly increased number of ordinal scanning pulses is produced by this tube per cycle.

In the foregoing description of the operation of this apparatus the electron beam of the tube 92 was scanned over the cathode mosaic target 9! through one complete cycle of the main scanning generator Hill and through twelve cycles of the auxiliary scanning generator lill so that the surface of the target 9! was substantially completely scanned by the electron beam. It is of course obvious that it may be desired to enter the values set into the keyboard of this apparatus, shown in Figure 1, into the register consisting of the tubes 60m, also shown in Figure I, more than once and for this purpose the target 9i 'of the tube '92 must be scanned as many times as it is desired to enter the values set into the keyboard into the registers cilia. The switches H6 and Hill, shown in Figure 5, may be used to control the number of times the target 9! of the tube 92 is to be scanned. Closing the switch Ht to the right so that the battery H4 is connected directly to the grid ID! of the capacitor charging tube I04 permits this tube its to charge the capacitor Hi so that a saw-tooth pulse is applied to the input of the current amplifier i'25 and the deflector coil 102 of the tube s2 is energized. A negative limiter tube i25a is connected across the deflector coil ii 02 for the purpose of limiting the negative swing of the pulses applied to the deflector coil 502. When the current amplifier input circuit is energized, current for energizing the deflector coil I62 flows through this amplifier H25 from the battery 12%, the positive terminal of which is connected to the coil terminal I00?) and the negative terminal of which isconnected'to the cathode of the amplifier I25. Thepositivetermi-nal of this battery is also connected through 'a resistor i250 to the screen grid electrode of the amplifier 125.

If it is desired to limit the lateral scan of the electron beam of the tube 92 to one cycle so that the values are introduced only once in the register, the coil m2 of themechanical deflector apparatus of the tube 92 must be energized by only one pulse each time the switch H 6, as shown in Figure 5, is closed tothe right. As explained above, closing the switch I Hi to the right renders the pentode ltd conductive so that the capacitor III is charged therethrough in a gradual manner resembling a saw-tooth. When this capacit'or 'l H' is charged to the breakdown 'voltage-of'the 15 thyratron I I1, this thyratron fires and discharges the capacitor III in an abrupt fashion. Inasmuch as the pentode I04 is in conductive condition as long as the switch I I6 is positioned to the right, the capacitor I I I will receive another charge through the tube I04 as soon as it is discharged by the thyratron II'I. As a result the electron beam of the tube 92 is scanned over the target 9| a second time and this operation may be repeated as long as the switch H6 is deflected to the right so that the value set into the keyboard of this apparatus may be translated into electrical pulses and transmitted to the register tubes 66 Ia a multiplicity of times simply by leaving the switch I it closed for the desired time interval and this time interval may be determined beforehand since the length of time required for charging the capacitor III through the pentode I04 is known. This charging time may be controlled by controlling the impedance of the pentode I04 during charging of the capacitor or by controlling the value of the resistor 1 I2, and where desired the resistor I i2 need not be connected in series with the capacitor IlI when this capacitor is discharged through the thyratron II'I since this thyratron may be connected directly across the capacitor III.

Where it is desired to operate the apparatus only one cycle, that is, to apply only one pulse from the charging of the capacitor HI to the H1 may be disconnected from the capacitor Iii by the switch I I9a so that the capacitor I I cannot discharge through this thyratron until after the switch H6 is moved to the left thereby ren-.

dering the pentode I04 non-conductive at which time the switch II9a may be closed and the capacitor III discharged through the tube iI'd. As was pointed out above, the switch I i5 is mechanically connected to switch its, but electrically insulated therefrom so that when the switch I I6 is positioned at the right the switch I553 is in contact with the terminal I62 and the switching tube I23 is in operative condition. However, when the switch H6 is at the left, the switch I61] contacts the terminal IBI and the tube I23 is inoperative as a switching device.

While only one amplifier tube 234 has been shown connected between the conductive plate 230 of the target of the cathode ray device 92. it is obvious that an amplifier consisting of several tubes connected in cascade, such as the amplifier shown on page 440 of the previously referred to book Television by Zworykin and Morton, may be employed. Furthermore, the input of this amplifier may be connected to the conductive plate 238 of the target 9| directly instead of through the capacitor 232, as shown in Figure 2, and in this case the grid of the tube 234 would be connected to the plate 230 and both the capacitor 232 and the resistor 23I omitted.

The target 9I of the tube 92 will take different forms depending upon the type of tube employed, and if the tube 92 is of the type commercially designated as an iconoscope then the sensitized surface 9% of the tube will comprise a cathode formed by evaporating a thin layer of silver upon an insulation disk of material, such as glass or mica. I'his thin layer of silver is evaporated on the cathode disk 244 after the tube has been evacuated and outgassed and the silver is then completely oxidized by a glow discharge in an. atmosphere of oxygen at low pressure. Thereafter caesium is added from the inside of the tube to activate the cathode and the tube is electromagnetic deflector coil I92, the thyratron baked for a short period after which anaddi tional small amount of silver is evaporated to the cathode and the tube is again baked. This process is well-known in the art, and further details thereof may be obtained from the previously mentioned book entitled Television.

Modified ordinal pulse switching tube control The switching tube 59's (Figure 10) may be provided with a pair or? beam deflecting electrodes 32% and 326 which are connected across the output resistor 2st of the amplifier 234 in series with the battery 322. This battery 322 supplies the beam deflecting potential to the deflecting electrodes 328 and 32% through the resistor 249 when no signal is applied to the input of the amplifier and normally deflects the beam or" the switching tube I9? downward against the apertured disk 323. However, when signal pulses are applied to the tube 234 from the electron beam device 82, as previously described, the potential drop across the resistor 246 due to the anode current or" the amplifier tube 2% caused by the signal, overcomes the potential of the battery 322 and permits the beam of the cathode ray switching tube it? to be projected through the aperture 324 of the disk 323 out through the anodes 282 and 203 between the deflecting electrodes led-i9?) and upon the selected target electrodes of the group 294-221.

Tens transfer circuit A tens transfer circuit is illustrated in Figure 11 in which the tens transfer is effected simultaneously with digitation in the cathode ray device 92 by selectively enabling tens transfer light indicla or spots in the proper ordinal relation under control of the register tubes. Referring to Figure 11, a bank of lights 3% is positioned with suitable light projecting lenses to project light spots on the lower portion of the oathode mosaic 98 of the electron beam device 92. The light apparatus 383 is provided with a plurality of lamps, each of which is positioned to project a light spot on a predetermined portion of the cathode mosaic 3i and each of which corresponds to and is controlled by one of the register tubes 69%, Fill, SE35, 9M, Iii-ti, IIiH, etc., respectively. The light spots projected from these lamps are in alignment with the ordinal rows of light spots projected on the cathode mosaic iii so that each ordinal row, except the first, is provided with a tens transfer lamp in the bank of lamps Said. These lamps may be selectively energized from the tens transfer electrodes of the register tubes 66L 'ifil, SUI 9M, mm, IIIii, etc, respectively. For this purpose the tens transfer electrodes (5624563, 564-665 of the tube Gti, for example) of the tubes GUI, Elli, 833i, dill, iii-Si, Hill, etc, may be connected to the grid and cathode of small thyratron tubes 3m, 3822, 354, 3535, etc., respectively, and the output circuits of these small thyratrons SE32, 3&3, 3%, 385, 386, etc, may be connected to the small lights 333, 3%, 3H and 3122, re-

spectively, in the light bank Silt.

Thus, when a tens transfer pulse is applied, for example, by the register tube (Bill, for the next order register the thyratron till is fired and the transfer light projects a small light upon the bottom portion of the cathode mosaic 9| just below the second order row of light spots on this cathode mosaic. As a result, when the beam of the electron beam device 92 scans the second row of light spots on the cathode mosaic 9'I', an adaccuse-9 "1'7 ditional electrical impulse corresponding to this tens transfer light spot is supplied to the amplifier 234 and is transmitted through the switchingtube I97 to the second order registertube Hi I.

Similarly, when the tens transfer electrodes of the tube in! are energized, the thyratron 392 is fired and the transfer light 3% projects a "small light spot just below the third order of the cathode mosaic 31, and, when the beam of the electron beam device 92 scans the third 'or- 'der row of vertical light spots, .it also scans this tens transfer light spot and the electrical impulse corresponding thereto is transmitted to the third order register tube 80!. Likewise, the lamps 3B9, SIB, 3H and M2 may be energized for tens transfer purposes by th register tubes 8M, 90], mm, HM, respectively, and the associated thyratron tubes 302, 303, 30s, 395 and 306, respectively, to supply tens transfer light indicia to the fourth, fifth, sixth and seventh orders in the selection tube .92 for transmission to the register tubes 90!, will, HUI, etc., respectively.

Modified transfer circuit of Figure 12 The embodiment of this invention employing the thyratron tubes 39! to .3055, inclusive, associated with the .register tubes 69! to Hill, inclusive,'respectively, asshown in Figure 11, may employ light sensitive thyratron tubes .3llla, 302a, 303a, 304a, etc., as shown .in Figure 12, in'place of the thyratron tubes 391,362, 303, etc., shown 'in Figure 11 for tens transfer purposes. Employing the light sensitive thyratron tubes 30m, 302a, 363a, etc., as "shown in Figure 12,

necessitates slight :changes .in the register tubes '601, !,801, etc., in that the tens transfer electrodes 16.62, 663, 6.54 .andlefiii of tube-60! are re- :placed by fluorescent coatings 30]?) adjacent to the thyratron tubes 3am, but inside of the envelope ;of the tube'eiii, so that these fluorescent coatings 36H) are energized and caused to "fluoresce by thecathoderay beam of the tube 63! for tens transfer purposes and -the fluorescent light from these :fiuorescent material patches is transmitted into the 'thyratron tubes '3fiI-a, the top :thyratron itube 3cm being energized 'by the fluorescent light from the associated patch 3811) for additive operations and the bottom patch and thyratron being energized for subtractive operations. The same arrangement is provided in the register tube iii! in which the electrodes such as "752, are replaced by two spots -or ,patches of fluorescent material on the inside of the tube directly behind the-position occupied .by these electrodes so that the upper thyratronEllZu is energized by a light from the fluorescent spot 3022) associated therewith for additive tens "transfer operation, and the lower spot 3E2?) is energized to transmit light to the lower 'thyratron 302a for subtractive tens transfer operations. While the fluorescent spots 3Ulb, 3932b, and 3031), etc., arepositionedon the inside of the register tubes 60'], 101, MEL-etc., in alignment and in the back of the corresponding tens transfer electrodes'tfii 663, 664 and 565, in the case of the tube "661, and the similar transfer electrodes inthe case of the register tubes Till, tube 881, etc., the thyratrons 3tia, 302a, 303a, etc., are on the outside of the register tubes 63!, PM, 88!, etc., respectively.

The thyratrons are of a small construction and each includes a cathode, 'a grid and an anode positioned in an envelope of glass or metal as desired. Where an-envelope of glassis employed, the outside thereof is 'coated with an opaque material, such as .quadag-overthe*entire surface except where light from the fluorescent material is to be admitted into the inside of the envelope. Care must be taken not to short circuit the lead-in .conductors to the cathode, grid and anode of the .thyratron with the aquadag coating.

Where a metal envelope is employed a suitable transparent window is provided through the metal for admission of light from the fluorescent spot associated with the respective lthyratron, and, furthermore, the leads 'to the cathode, grid and .anode of the .thyratron must be insulated from the metal envelope by means of suitable glass beads or glassLheaders.

'Thecathodes of the thyratrons 3.0 Ia,.302a;303a, are all connected together to a tap 325 of the voltage divider 325. The voltage divider 32$ is connected acrossa suitable source of direct current voltage 321, such as a battery or rectified alternating current supply or thelike. The negative terminal of the voltage divider 3261s connected to the grid electrode of all of the 'thyratrons 'ililla, 302a, 303a, etc., and the anodes of these thyratrons are connected to the positive :terminal of the voltage divider 323 through the fluorescent lamps 328, 329, 330 and associated resistors 33 I, 332, 333, respectively.

The fluorescent lamps 328, 329 and 330 .are small bulbs each havingasmall quantity of mercury'therein which is ionized by a potential across the bulb controlled by the associated thyratron and the ionized mercury generates ultraviolet light which energizesa fluorescent chemical coating of material, such as Willemite, zincsulphide and the"like,.coated on the inside of the bulbs 3.28, .328 and 330, respectively.

Thus, when the beam of the register tube .60.! is deflected to the .position of electrodes'66ll--6,65., it is in position to energize the .fluorescentspot 3011) which replaces the electrode 354-665. When the spot 3012) is thus energized, .it transmits light .into the .thyratron 3llla which causes this 'thyratron to -fire since the light transmitted into the thyratron ionizes the gas therein and .causes the grid of the tube to lose control. .As a result, the current flowing through the thyratron 301a from the source .32! increases very rapidly and this increased currentincreases the voltage drop across the resistor 33I and this increased voltage drop fires the fluorescent lamp 323.

The fluorescent lamps .328, 329, v330,, etc., are

' associated with the cathode mosaic'fil of the electron beam tube '92 shownin Figures .1 and .2, in such a .way that the lamp 328 (when illuminated projects a light spot 328a on the cathode mosaic 8! directly below the second order vertical row of light spots projecting on this cathode mosaic on the light projecting apparatus 29, a lamp 329 ispositioned to proiecta light spot 329a .on the cathode mosaic 9i directlybelow the third order vertical row of v lightspotsprojected on thiscathode mosaic by the apparatus 29 .and1lamp330 .is arranged to project .a light spot 3390. directly below the fourth order light spots on the cathode mosaic 9!, etc. Thus, it willbe seen that when thetens transferlight spot .328ais proj ected below the second order row of light spotsonthecathode mosaic 51, when the thyratron 302a associated with the register 17%! is fired, the lamp 329 is energized and projects a light spot 329a below the third .order row of light spotson .the mosaic 9| and when thethyratron 3t3a.is;fired, the lamp 339 is energized .and projects a light spot 33% just below the fourth order row of vertical light spots on the cathode mosaic 9!. Of course, it is obvious that the thyratrons associated with the register tubes Sill, Itiii, lllll, etc., are connected in the same manner as the thyratrons sum, 302a, 303a, etc., and are provided with circuit-s to control lamps such as 323, 329, 330, so that the fifth, sixth, seventh, eighth, etc., orders rows of light spots on the mosaic 9! will of course also be provided with tens transfer light spots such as 328a, 329a, 330a, as described above.

After the electron beam of the tube 92 scans the cathode mosaic completely from the righthand side to the left-hand side, as explained above, it impinges upon a pair of electrodes 33m formed in the lower left-hand corner of the oathode mosaic 91 and insulated from this cathode mosaic by suitable insulation means. These electrodes 33m are connected to the input of a suitable amplifier 332a, the output of which is connected to the relay 333a connected between the voltage divider 325 and the source of current supply 327 and as a result when the electron beam of the tube 31 closes the circuit between the electrodes 33! the amplifier 332a causes the relay 3330, to open the contacts thereof and interrupt the circuit between the voltage divider 328 and the source of current supply 32?, thereby interrupting the anode current to the thyratrons 3i? i a, 302a, 303a, etc., at the end of the scanning cycle and permitting each of the thyratrons to deionize.

As a result, when the electron beam of the tube 92 leaves the contacts 33m after momentarily impinging thereon, the thyratrons 30hr, 332a, 393a, etc., will be ole-ionized, and, when the relay 333a is de-energized so that the contacts thereof close and apply the potential from the source 32'! to the voltage divider 326, the grid electrodes of each of the voltage thyratrons will have regained control. Consequently, these thyratrons will not be in firing condition until again energized by the associated fluorescent spots for tens transfer purposes.

It will be observed that the operation of the above tens transfer circuit must be rapid enough so that the tens transfer spots 328a, 329a,, 33%, etc., are in position below the second, third and fourth order light spot rows on the mosaic 9! before the electron beam of the tube 92 starts scanning these vertical rows of light spots. For example, after the electron beam of the tube 92 scans over the first row of light spots in the first order on the mosaic 9| if there is to be a transfer into the second order register tube '50! the light spot 328a must be in position below the second order row of light spots on the mosaic 9! before the beam from the tube 92 starts scanning this second order row of light spots.

In order to insure sufficient time for this operation, a suitable limiting tube 334 (Figure 6) is provided in the circuit of the deflection coil I33 to cut off the lower portion of the scanning sawtooth wave applied to this coil M33, as shown in Figure 6A, so that only portions 335 of the sawtooth waves applied to this coil will be eifective in moving the electron beam of the tube 92. As a result, the time interval 338 will be a time of inaction so far as the electron beam of the tube 92 is concerned inasmuch as the electron beam has been acted on by the top sloping portion of the scanning wave 335. The beam is blanked out at the top of the wave 335 and when it is restored it is at the bottom of the cathode mosaic 9| beneath the tens transfer light spots 328a, 329a, etc., and rests there substantially during the time interval 336 until the saw tooth wave is of a voltage sufiicient to overcome the limiter tube 33% and reaches the bottom of the scanning wave 335. During the interval 335 the light spot 3255a is flashed on the cathode mosaic 9i and is in position thereon when the electron beam is started on its scanning cycle so that this light spot 323a causes an electrical pulse to be transmitted through the amplifier 234, as shown in Figure 2, the apparatus 23? and this electrical pulse is added to the register it 1. Likewise, after tens transfer thyratron 302a associated with the register tube 10! is fired, the lamp 329 projects a transfer light spot 323a on the mosaic SI and so on.

Counter A counter of the type disclosed in our application, Serial No. 611,608, filed August 20, 1945, may be employed in accordance with this invention with a slightly modified form of electron tube, suchas tube 92 shown in Figures 12 and 15. This counter is designated by the reference numeral 380 (Figure 15) having input terminals 38! and 382 connected across a resistor 383. The input terminal 381 is also connected to one of the electrodes 33|b positioned along the side of the target 9! of the tube 92, as shown in Figure 12, and the terminal 382 is connected to the positive terminal of a battery 385, the negative erminal of which is connected to the cathode of the electron gun of the tube 92. With this arrangement the number of scanning cycles completed by the tube 92 are counted by the item counter 38% since each time the beam of the tube 82 scans the target 9!, it energizes the input of the counter 389 by completing a circuit of the revolutions counter 38%! when it engages the auxiliary electrode 3311). It will be apparent that 13 pulses are required for completely scanning the target 9! of the tube 92 in this case since twelve pulses are required for scanning the ordinal arrays of light spots, as previously described, and the thirteenth pulse is required for scanning the beam of the tube 92 over the electrode 33ib. This, of course, presents no difficulty since the pulse generator iill' (Figure 6) and tube i23 (Figure 5) previously described for generating the twelve pulses may be arranged to generate thirteen pulses instead of twelve.

Control of ordinal entry of pulses For multiplying and dividing operations it is desirable to enter values from the tube 92 in various selected ordinal positions. For this purpose a tapped battery or other source of electric voltage may be provided between the terminal liita (Figure '7) connected to the battery I35 and resistor I96 and the terminal |98a of the deflector electrode i98 of the tube l9! (Figure 8), the terminals i957; (Figure 7) and IBM (Figure 8) remaining connected as before. Such a tapped battery a, is shown in Figure 7a and the purpose thereof is to shift the position of the beam of the tube It? so that when the first tap I35?) of this battery is connected by the switch 5350 the beam of the tube it? will impinge initially on the tens order electrode 2iifi29l instead of on the units order electrodes 235-235. In other words, the beam is shifted or biased one step by connecting the battery ISEia to the first tap I951) and applying the potential from this tap to the voltage divider lstid, the terminals I952 and I951 are connected to the terminals 295a (Figure 7) and [98a (Figure 8), respectively. Connecting the battery to the second tap g through switch l95h wi1l advance. the beam of the tube [91 two steps, that is, to electrodes 253-259 from theelectrodesQEBG-ME andconnecting the third tap I 95i of the battery will advance the beam of the tube I] to electrodes 2I02H on the electrodes 204-225. In this manner, this apparatus' may be conveniently employed for multiplication since the pulses that would-normally. be fed into the circuit of the electrodes 2d l2ii5 of. the switching tube 397 may be fed into the electrodes 206-40? or 2fi8--2G9 or electrodes Mil-2H instead, and of course, the following electric. pulses will be fed into the succeeding electrodes of the tube l9! asthe beam of this tube isadvanced over. the tube electrodes in step. fashion, as previously described.

Variable pulsedelay control of ordinal entry Inasmuch as the operation of the scanning. circuits of. thetube S2 and the operation of the beamdefiection circuit of the switching tube l9! areboth controlled from a central oscillator H38, shownin Figure-5, these tubes will have a definite timed relation in their operation so that the electrical pulses produced. in the output circuit of the tube 92 and amplified by the amplifier 234 will be fed into theswitching tube l9? to be redistributed to the respective registers at the proper timed intervals. In fact, it may be desirable tointroduce a variable time delay elementinto the input or output circuit of the amplifier 23450 that the time of the pulses received from the tube 92'may be slightly variedwith respect to the deflection of the electron beam of the switching tube [97' andthis may be accomplished by placing av time delay element such as aniinductance, or a resistor-capacitor circuit orv an inductance-capacitor circuit into. either the.

tacts284205 of the switching tube It? may in fact be fed into the contacts 2ii52@'lor into the contacts 298-469 as desired and so on.

Plural cycle control A modified form ofpulse generating circuit is shown. in Figure l3zwhich may be employed for controlling: the sequence of: operation or the tube I04 (Figure 5) by controlling the grid bias of this tube from the output resistor 359 or this circuit (Figure 13) may be used to produce a selected number of pulses in the output of. tube I23 (Figure 5). This pulse generating circuit employsa capacitor charging tube 359' (either gas or vacuum) which is provided with a cathode 35!, a grid electrode 352 and. ananode 353. A grid bias battery 354 is connected between the cathode 35!. andthegrid 352 through: a: switch 3.55-anda resistor 355 so that when the switch 35.5 is closed thev tube 35% is conductive. One side of the capacitor 351 is connected to the battery 358. by the resistor S69 and thev switch 356. The gas discharge tube 36! is provided with three electrodes, namely, a cathode 362, an anode 353 and a control electrode 354. The control' electrode. 354 is connected through a capacitor 3.65. and. through the switch 366 to the battery 35.8; the. anode 363 is connected to the 22'? capacitor 357' and, the: cathode 362.. is connected. to. one terminal of the output resistor 359', the other. terminal of which is connected tothe anode 353 of the. tube 350. The. switch 355'is mechanically ganged: to the main control switch 355;. and when the switch 366 is closed the gas tube 36I- is fired by the charging pulse flowing into the relatively. small capacitor 355. Charge ing of the capacitor. 35'! is initiated when the tube 35! fires and when the capacitor 351 is charging a pulse is produced across the output resistor 359. When the capacitor 351 is substantially-charged another capacitor 3631) connected.

between the resistors 3E9 and-363a is charged to provide the required grid pulse. for firing the next gas discharge tube 359 which is the same type of tube as 36!; will be. fired if the switch 358 is closed. If the switch 368 is'closed, an electric potential is applied from the cathode to the anode of the gas tube 563 through the resistor 31!: sufficient to ionize the gas tube 359 if the grid thereof is properly energized, and. permit the charging of the capacitor 361 from the battery 358- through the resistor 35%, tube 3.53 and switch 358, thus producing a second pulse through the resistor 359. A third pulse. may be produced through thisv resistor by charging the third capacitor 314:

if the switch 3'55 is closed since a firing potential is applied to the grid of the gas tube 313 in the charging of the capacitor 369a after the capacitor 35! is charged orsubstantially charged. Additional pulses may be produced through the output resistor 659 by adding additional capacitors,

resistors and gas discharge devices depending upon the number, of pulses it is desired to produes in an operation.

While the invention: has beenillustrated and described in connection with a preferred em-' bodiment thereof,,it is capable of other varia tions'andmodifications within the scope of the claims appended hereto.

We claim:

1-. In an electronic calculator, aregistering'd vice, a cathode ray tube having a light-responsive screen and an. electron gun for producing a screenescanning electron beam, means for producing a light indicia on said screen representinga number, means controlled by said electron beam; for. transmitting electrical pulses representing said number to said registering device in response. to scanning of said light indicia on saidscreen, and an electric circuit controlled by said registering device for producing additional light indicia. on said, screen.

. 2. Anelectronicv calculator. comprising in combination; an electron tube having an electron emissive target and having means for scanning said target with acceleratedelectrons and also having an output circuit; means for energizing an ordinal array of spots on said electron emissive target representing values from "1 to 9 to cause said spots to emit electrons when scanned by said accelerated electrons; a plurality of orders of electronic registering devices; an electronic switching device for coupling said electron tube output circuit selectively to different orders ofjsaid electronic registering devices, and pulse generating means for controlling said electrontube scanning. means and said electronic switching device in timed relation.

3. An electronic calculator comprising in combination: a keyboard; an optical system controlled by said keyboard; an electrontube having an electron. emissive target and having This second gas tube 369- means for scanning said target with accelerated electrons and also having an output circuit; means associated with said optical system for energizing an ordinal array of spots of said electron emissive target representing values from 1 to 9 to cause said spots to emit electrons when scanned by said accelerated electrons, a plurality of orders of electronic registering de vices, an electronic switching device for coup ing said electron tube output circuit selectively to different orders of said electronic registering alevices, and pulse generating means for controlling said electron tube scanning means and said electronic switching device in timed relation.

4. An electronic calculator comprising in combination: an electron tube having an electron emissive cathode mosaic target and having means for scanning said target and also having an output circuit; means for projecting beams of radiant energy upon said electron emissive target to produce ordinal sets of pulses representing values from i to 9 in said output circuit when said target is scanned; a plurality of orders of registering electronic devices; an electronic switching device for coupling said electron tube output circuit selectively to difierent orders of said registering electronic devices; and pulse generating means for controlling said electron tube scanning means and said electronic switching device in timed relation.

5. In an electronic calculator, a cathode ray tube having a light responsive screen and an electron gun for producing a screen scanning electron beam, means for producing a plurality of columns of light patterns each of incremental character on said screen for scanning by said beam and each of said columns representing a number, a registering device for receiving incremental signals derived by scanning said columns of light patterns on said cathode ray tube screen for entry therein of the numbers represented by the signals, and an electrical circuit controlled by said registering device for producing an incremental signal on said screen representing a transfer increment for scanning by said beam.

6, In an electronic calculator, a registering device, a cathode ray tube having a light responsive screen and an electron gun for producing a screen scanning electron beam, means for producing a plurality of columns of light indicia on said screen, each of said columns representing a number, means controlled by said electron beam for transmitting numbers of pulses to said registering device in response to scanning of said screen, and an electrical circuit controlled by said registering device for producing additional light indicia in one of said columnar light indicia on said screen.

"i. In an electronic calculator, a registering device, a cathode ray tube having a light responsive screen and an electron gun for producing a screen scanning electron beam, means for producing a column of light dots on said screen representing a number, means controlled by said electron beam for transmitting values as represented by said column of light dots to said registe ing device in response to scanning of said screen, an electrical circuit controlled by said registering device for producing an additional light dot on said screen as a part of said column.

8. In an electronic calculator, a registering device, a cathode ray tube having a light responsive screen and an electron gun for producing a screen scanning electron beam, means for selectively producing a plurality of orders of incremental light patterns on said screen representing a plural digit number, means for scanning said light patterns on said screen order by order by said electron beam for transmitting numbers of pulses to said registering device in respo s o S n g of said screen, and an electrical circuit controlled by said registering device for producing additional incremental light indicia in one of said orders on said screen.

9. An electronic calculator comprising in combination an electro-optical device for producing successive ordinal series of incremental electrical pulses corresponding to certain predetermined numbers, a plurality of ordinally arranged registering devices, a switching device connected between said electro-optical device and said registering devices, a timing device comprising an electron discharge device connected to control said switching device for entry of the successive ordinal series of electrical pulses produced by said electro-optical device into successive orders of said registering devices, and an electrical circuit for selecting the ordinal position of entry of values into said registering devices.

10. In a calculator, selection mechanism comprising a cathode ray tube having a light responsive screen and an electron gun for producing a screen-scanning electron beam, and also comprising an optical system for producing an ordinally arranged light pattern on said screen, said optical system including means for producing a differential light pattern for each order of a plural figure value with each ordinal pattern confined to a given ordinal area of the screen, means 2 for controlling said electron beam to scan each ordinal area as a unit and to scan said ordinal areas in succession to produce a differential signal for each ordinal area, with respective difierential signals occurring as a sequence, a plural order difierential signal responsive registering ,on said screen, said optical system including means for producing a differential light pattern of columnar arrangement for each order of a plural figure value with each ordinal pattern confined to a given ordinal area of the screen,

means for controlling said electron beam to scan each ordinal area as a unit and to scan said ordinal areas in succession to produce a differential signal for each ordinal area, with respective differential signals occurring as a sequence, a plural order differential signal responsive registering means, and means for transmitting said sequence of signals to the respective orders of said registering means.

12. In a calculator, selection mechanism comprising a cathode ray tube having a light responsive screen and an electron gun for producing a screen-scanning electron beam, and also comprising an optical system for producing an ordinally arranged light pattern on said screen, said optical system including means for producing a each ordinal area as a unit and to scan said ordinal areas :in succession to produce a differential signal for-each ordinalarea, with respective differential signals occurring as a sequence, a plural order differential signal responsive registering means including ordinal tens transfer means, meansfor transmitting said sequence-of'signals to. the resp ective orders of said registering means, and means controlled by said ordinaltens transfer 'means 'for producing a tens transfer light pattern on said screen in coordinated ordinal relation to said 'firstenamedjlight pattern.

13. In acalculator, a cathode ray'tube having a light responsive screen and anelectron gun for producing a screen-scanning electron beam, means for producing lightindicia on said screen in an ordinal array to represent aplural order value, means for causing said beam to scansaid indicia order'by orderpa plural order register, means "for transmitting ordinal .signalsfrom said cathode ray .tube to said register in ordinal fashion, said register includingor'dinal ,tenstransfer means for producing ordinal transfer signals, and transfer signal responsive means for .producingtens transfer lightindicia on said screen in coordinated ordinal relation to said firstnamed light indiciafor scanning by said beam.

14.In a calculator, selection mechanism comprising a cathoderay tube having a light responsive-screen and an electron gun for producing a screen-scanning electron beam, and also comprising anoptical system for producingan ordinally arranged light pattern on said screen, said optical system including means for producing a diiferential light .pattern for each order of a plural figure value with each ordinal pattern confined to a given ordinal area of the screen, means for controlling said electron beam to scan each ordinal area as a unit andto scan said ordinal areas in succession to producea differential signalfor each ordinal area, with respective differential signals occurring as a sequence, a plural order .difierential signal responsive registering means, means for selecting the orders of said registering means to receive the difierential signals, and means for transmitting said sequence of signals to selected orders of said registering means.

15. In a calculator, selection mechanism comprising a cathode ray tube having a light responsive .screen and an electron gun for producing a .screemscanning electron beam, and also comprising a differentiallysettable optical system for producing an ordinally arranged light pattern on said screen, said Optical system including meansfor producing a difierentiallight pattern of columnarflarrangement for each order of a plural figure value with each ordinal pattern confined to a given ordinal area of the screen, means for controlling said electron beam to scan each ordinal area as a unit and to scan said ordinal areas in succession to produce a differential signal for each ordinalarea, with respective dififerential signals occurring as a sequence, a plural order difierential. signal responsive registering means, means for selecting the orders of said registering means to receive the differential :signals, and means for transmitting said sequence of signals to selected orders of said registering means.

16. In a calculator, selection mechanism-comprising a cathode ray tube having a light responsive screen and an electron gun for producing. a screen-scanning -electron beam, and also comprising .an optical system for producing an ordinallyarranged light pattern onsaid-screen, said optical system. including means for-producing a order ,difierential signal responsive registering means including ordinal tens transfer means, means'for selecting the orders of said registering means to receive the differential signals, means for transmitting said sequence of signals to selected orders of said registering means, and

means controlled-by said ordinal tens transfer means for producing a tens transfer light-pattern on said screenin coordinated ordinal relation to said first-named light pattern.

17. I-n-an electronic calculator, selection mechanism comprising a cathode ray tube having a light responsivescreen and an electron gun "for producing an electronbeam, a differentially settable optical system for producing a plurality of groups of light spots on a predetermined path on -said screen, each of said groups of spots representing a different order number of a plural order number, means for scanning said beam over said predetermined path to produce groups of electrical pulses corresponding to the said groups of light spots, an output circuit, and connections for connecting said output circuit to said cathode ray tube for utilizing said electrical pulses.

'18. 'In an electronic calculator, selection mechanism comprising a cathode ray tube having a light responsive screen and an electron gun'for producing an electron beam, differentially settable means for producing a plurality ofgroups of light spots on said screen, each of said groups of spots representinga difierent order number of a plural order number, means for scanning said beam over'said groups of light spots order by order to produce groups of electrical pulses corresponding to the orders of said plural order number, means for generating electrical oscillations for controlling said scanning means, an output circuit, and connections for connecting said output circuit to said cathode raytube forutilizing said electrical pulses.

l9. In an electronic calculator, the combination of a selection mechanism comprising a device for representing a pluralfigure number by plural columnar patterns of electrically charged areas, said device having means for producing electrical pulses correspondingtosaid electrically charged areas, each of the columns of said plural columnar patterns representing a figure of said plural figure number, said device having electrical controls for arranging said groups of pulses so that each of said groups represents one of thelfigures of said plural figure. number, said controls also having means for arranging said groups of pulses in the same sequence as the figures of said plural figure number, a register adapted to-countzsaid pulses, andan electric circuit connected between said electrical device and said registerfor; feeding said groups of pulses to said registerbeginning withthe group corresponding to the lowest order of said plural figure number and-continuing with the other of saidgroups order by order.

20. In an electronic calculator, the combination of a selection mechanism comprising.adevicefor representing a plural, figure number by patterns of electrically charged areas, eachof saidpatterns representing a figure of said plural figure number, an electrical device for producing a plu-. 

